I use Angular 2 in production since November 19, 2015 (alpha.46). Currently I've built 3 web apps (40, 60 and 20 components each), 3 mobile apps (with Ionic 2) and my employer have plans for more apps.

Breaking changes during alpha stage were expected, so I didn't have issues with it.

Most positive things I want to highlight:

1. Components are encapsulated and truly reusable (and without dependencies hell).

2. You don't need any "bridges" anymore to use 3-rd party JS libraries inside your Angular app. Nothing need to be "angularized" - twbs, D3, all just works out of the box. Maybe it's even most important part for me.

3. Idea of `(events)` and `[attributes]` is awesome, works really effective and makes code much more easy to read.

4. Performance is great.

5. Community is friendly and have a lot of fun and patience, even to newbies.

6. TypeScript gives a lot of bonuses with zero price - you don't need to learn anything (you can just rename js to ts and it will work) and additions to JS are simple and powerful.

7. Cool abilities like AOT-compilation, server-side rendering and tree-shaking.

Congrats to the all devs who are using Angular, congrats to the Angular team! :)